Press Releases

Jan. 30, 2020

Real-time Monitoring Technology of β-ray emitted radionuclide (90Sr-90Y) in Water Has Been Successfully Developed—That Technology Has Begun to Be Used as a Monitor for Checking Radiation Levels in the Drainage Channels Within the Site of Fukushima #1 Nuclear Power Station—

Within the site of TEPCO’s Fukushima # 1 nuclear power station (1F), because of the possibility for leaks of contaminated water in drainage channels, sampling water in those channels has been conducted to measure the beta (β)-ray emitted radiation of strontium 90, which is often high in such contaminated water.

However, in their current situation of 1F, most of their monitors cannot distinguish between β and gamma (γ) radiations. Therefore, in order for the power station to ensure immediate response and high efficiency in radiation monitoring, there was a need for the development of a more convenient, novel real-time monitoring technology that allows for distinguishing β rays, which are difficult to be directly measured because their distance to travel in water (i.e., their range) is too small, from γ rays, which are originated from radioactive fallout accumulated on the ground resulting from atmospheric testing of nuclear weapons or from nuclear power station accidents.

Under such circumstances, JAEA and other institutes succeeded in the development of a fiber-type monitor that provides real-time distinguishing between β and γ radiation. The achievement of real-time monitoring of β radiation will require neither on-site sampling nor analysis of drainage channels, and furthermore, will lead to expectations of not only accelerated estimation of whether leakage of contaminated water occurred but also reduced burdens on workers in the field.